Fair Value of Financial Instruments - Schedule of Fair Value Assets and Liabilities Measured on Recurring Basis (Details) - USD ($) $ in Thousands	Jun. 30, 2025	Dec. 31, 2024	Dec. 31, 2023
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Total available-for-sale fixed-maturity securities	$ 3,096,708	$ 2,946,126
Equity securities	24,867	27,144
Cash and cash equivalents	621,198	687,821
Separate account assets	2,318,492	2,209,287
Separate account liabilities	2,318,492	2,209,287	$ 2,395,842
Fair Value, Recurring Measurements [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Total available-for-sale fixed-maturity securities	3,096,708	2,946,126
Equity securities	24,867	27,144
Trading securities	2,969	3,011
Cash and cash equivalents	621,198	687,821
Separate account assets	2,318,492	2,209,287
Assets, fair value disclosure	6,064,234	5,873,389
Separate account liabilities	2,318,492	2,209,287
Liabilities, fair value disclosure	2,318,492	2,209,287
Fair Value, Recurring Measurements [Member] \| Level 1 [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Total available-for-sale fixed-maturity securities	3,720	3,787
Equity securities	24,867	24,598
Cash and cash equivalents	621,198	687,821
Assets, fair value disclosure	649,785	716,206
Fair Value, Recurring Measurements [Member] \| Level 2 [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Total available-for-sale fixed-maturity securities	3,092,988	2,942,339
Equity securities		1,003
Trading securities	2,969	3,011
Separate account assets	2,318,492	2,209,287
Assets, fair value disclosure	5,414,449	5,155,640
Separate account liabilities	2,318,492	2,209,287
Liabilities, fair value disclosure	2,318,492	2,209,287
Fair Value, Recurring Measurements [Member] \| Level 3 [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Equity securities		1,543
Assets, fair value disclosure		1,543
Fair Value, Recurring Measurements [Member] \| U.S. Government and Agencies [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Total available-for-sale fixed-maturity securities	9,669	9,503
Fair Value, Recurring Measurements [Member] \| U.S. Government and Agencies [Member] \| Level 2 [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Total available-for-sale fixed-maturity securities	9,669	9,503
Fair Value, Recurring Measurements [Member] \| Foreign Government [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Total available-for-sale fixed-maturity securities	182,436	166,424
Fair Value, Recurring Measurements [Member] \| Foreign Government [Member] \| Level 2 [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Total available-for-sale fixed-maturity securities	182,436	166,424
Fair Value, Recurring Measurements [Member] \| States and Political Subdivisions [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Total available-for-sale fixed-maturity securities	112,800	113,569
Fair Value, Recurring Measurements [Member] \| States and Political Subdivisions [Member] \| Level 2 [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Total available-for-sale fixed-maturity securities	112,800	113,569
Fair Value, Recurring Measurements [Member] \| Corporates [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Total available-for-sale fixed-maturity securities	1,919,007	1,825,108
Fair Value, Recurring Measurements [Member] \| Corporates [Member] \| Level 1 [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Total available-for-sale fixed-maturity securities	3,720	3,787
Fair Value, Recurring Measurements [Member] \| Corporates [Member] \| Level 2 [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Total available-for-sale fixed-maturity securities	1,915,287	1,821,321
Fair Value, Recurring Measurements [Member] \| Residential Mortgage-backed Securities [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Total available-for-sale fixed-maturity securities	572,666	486,557
Fair Value, Recurring Measurements [Member] \| Residential Mortgage-backed Securities [Member] \| Level 2 [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Total available-for-sale fixed-maturity securities	572,666	486,557
Fair Value, Recurring Measurements [Member] \| Commercial Mortgage-backed Securities [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Total available-for-sale fixed-maturity securities	97,549	99,445
Fair Value, Recurring Measurements [Member] \| Commercial Mortgage-backed Securities [Member] \| Level 2 [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Total available-for-sale fixed-maturity securities	97,549	99,445
Fair Value, Recurring Measurements [Member] \| Other Asset-backed Securities [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Total available-for-sale fixed-maturity securities	202,581	245,520
Fair Value, Recurring Measurements [Member] \| Other Asset-backed Securities [Member] \| Level 2 [Member]
Fair Value Balance Sheet Grouping Financial Statement Captions [Line Items]
Total available-for-sale fixed-maturity securities	$ 202,581	$ 245,520

Fair value portion of asset recognized for present right to economic benefit.

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